Management of stable flies in cattle feedlots with releases of parasitic wasps

During 1992, adult stable fly populations were sampled in 25 Kansas feedlots. A native stable fly parasitic wasp, Spalangia nigroaenea, was released in 19 of these feedlots. Stable fly populations were reduced up to 48% and parasite emergence was increased 21% when compared with feedlots where S. nigroaenea was not released. The percentage of total parasites that were S. nigroaenea nearly doubled in the release feedlots, compared to the nonrelease feedlots. This parasitic wasp has shown considerable promise for stable fly control in cattle feedlots. Overall, sampling and parasite costs averaged 32 cents per animal for the season

Efficacy of using parasitic wasps to control stable flies in Kansas feedlots

Release of parasitic wasps has resulted in stable fly reductions averaging 28, 42 and 38% for 1991, 1992, and 1993, respectively, with considerable variation from feedlot to feedlot. Costs for parasites plus sampling averaged $.23,$.32 and $.26 per animal during 1991, 1992, and 1993, respectively. Because stable flies are estimated to cause losses of$5.00 to $30.00 per animal, these costs are very reasonable

Effects of two temperature storage regimes on the efficacy of 3 commercial gel baits against the German cockroach, Blattella germanica L. (Dictyoptera: Blattellidae)

Background: To compare the effectiveness of 3 commercial gel bait formulations containing fipronil (Goliath© Cockroach Gel 0.05% AI), chlorpyrifos-A (Clean Bait© Gel, 2% AI), and chloropyrifos-B (Serpa© Gel 2% AI) against German cockroaches (Blattella germanica) when stored at 23°C and 30° C after treatment. Methods: Laboratory bioassays consisted of placing groups of fifteen cockroaches (a random combination of adult, mixed sex and large nymphs-stage 6) into a 5 L cylindrical plastic container with one drop of product (avg 0.10 g ± 0.01 g) applied to a 76 mm × 26 mm glass microscope slide affixed to the bottom of each container (one product tested per container). Cumulative mortality was assessed at 6 h, 1, 2, 3, 4, and 5 d after application. To determine the further effects of storage temperature after treatment on residual activity of the gels, a drop of each product was applied to separate glass microscope slides and stored at either 23° C (warm) or 30° C (hot) under dark conditions for 0, 1, 7, 14, 30, 45, 60 and 90 d after application. Results: Freshly applied baits (day 0) containing fipronil provided complete cockroach mortality (100%) within 5 d whereas chloryrifos-A and chlorpyrifos-B provided ?72% and 88% mortality, respectively. Generally, cockroach mortality was greater when gels were stored at 30°C compared with 23° C. Conclusion: The fipronil gel formulation proved to be as efficacious as the chlorpyrifos gels and in some instances surpased the latter formulations depending on storage time and temperature by providing ?90% mortality at 90 d post treatment

Acaricidal activity of Satureja thymbra L. essential oil and its major components, carvacrol and ?-terpinene against adult Hyalomma marginatum (Acari: Ixodidae)

PubMed ID: 20303667The acaricidal activity of a volatile essential oil hydrodistillate of Satureja thymbra L. (Lamiaceae) and its major constituents, carvacrol and ?-terpinene, were evaluated against field-collected unfed adult Hyalomma marginatum. The distillate was tested against this tick species at 5, 10, 20, and 40 µL/L while the two major components were each tested at 10 µL/L. Generally, tick mortality to the S. thymbra distillate increased with concentration and exposure time. Ticks exposed to vapors from cotton wicks containing at least 40 µL/L resulted in complete (100%) mortality at 3. h. The lower concentrations provided ?90% mortality at 3. h post treatment with complete mortality at 24. h. Knockdown was observed only in the carvacrol and ?-terpinene treatments. Ticks exposed to carvacrol-treated wicks produced >93% knockdown at 3. h but at 24. h approximately 57% were dead. The ?-terpinene treatment produced ?90% knockdown at 105. min through 3. h but at 24. h only about 87% of the ticks were dead. © 2010 Elsevier B.V.Firat University Scientific Research Projects Management UnitThe authors are grateful to the Scientific Projects Administration Unit of Akdeniz University (Antalya, Turkey) for financial support. -

Surtos por Stomoxys calcitrans em gado de corte no Mato Grosso do Sul

A expansão da indústria sucroalcooleira tem levado à instalação de usinas de álcool em áreas tradicionalmente ocupadas pela pecuária de corte na região Centro-Oeste do País. Surtos pela mosca-dos-estábulos (Stomoxys calcitrans) em bovinos Nelore têm sido relatados nos últimos dois anos em Mato Grosso do Sul, associados a estas usinas. Visitas em propriedades pecuárias e usinas foram realizadas em meados de novembro 2009, ao final de surtos por S. calcitrans ocorridos nos municípios de Angélica e Ponta Porã, MS. Entrevistas, observações e coletas de imaturos de dípteros foram realizadas nos locais e o material entomológico coletado foi levado ao laboratório para posterior emergência. Elevadas infestações pela mosca-dos-estábulos e comportamento de agrupamento dos bovinos foram observados. Sítios de reprodução foram encontrados nos locais e a emergência de S. calcitrans foi constatada nas amostras coletadas tanto nas fazendas como nas usinas. O conjunto de informações, observações in loco e resultados das amostragens possibilitaram realizar uma abordagem epidemiológica preliminar sobre a dinâmica dos referidos surtos por S. calcitrans e discutir potenciais fatores de risco